This invention relates to vessels with airfoils and more particularly to a vessel with retractable airfoils that can have both surface-effect lift and airfoil lift to raise the vessel above water for decreasing power relative to speed of propulsion of the vessel and for increasing its smoothness of ride.
Lifting a vessel above water by increasing speed of its propulsion has long been a design objective for overcoming a marine coefficient of increase in power required per length of a water craft with idealized wave-making and wave-breaking proportions of the vessel under five-hundred feet long. Power required per weight of an idealized ship-proportioned displacement hull having a widening front third and a narrowing aft two-thirds of its length at waterline for wave control multiplies approximately four times with decrease of length from five-hundred feet to one-hundred feet long. To compensate for the marine coefficient of impediment from wave-control-shortness, vessel designers have employed variously planing hulls, hydrofoil structures and airfoil wings to lift vessels partially out of, onto a top surface of or above water in which the vessels are propelled.
Hydrofoils have drawbacks related to resistance of water density and air cavitation.
A ground-effect lift in close proximity to a surface is a more efficient lift means than a hydrofoil because it requires less speed and power to achieve the speed for lift of the vessel as a result of a partial entrapment of and pressurization of air between a bottom surface of a ground-effect wing and a surface that is entrapment-effectively close to the bottom surface of the ground-effect wing. Ground effect over water is achieved from riding on air that is entrapment-effectively pressured against a closely proximate surface of water.
There is no known vessel having an extendable ground-effect wing with a traveling incline that pressurizes air downwardly against a surface of water in a manner taught by this invention.
Examples of most-closely related known but different devices are described in the following patent documents:
Patent No.InventorIssue Date5,111,766OrtemondMay 12, 19924,926,778JohnstonMay 22, 19904,736,700Ishimatsu, et al.Apr. 12, 19884,284,027MontezAug. 18, 19814,237,811MontezDec. 09, 19805,636,585SchulzJun. 10, 1997D464,310Fuller, et al.Oct. 15, 20023,648,641Normand, Jr.Mar. 14, 1972  913,515LakeFeb. 23, 19093,786,774GabelJan. 22, 19742,887,979J. BaderMay 26, 19593,164,117LopezJan. 05, 19652,274,200HillFeb. 24, 19425,404,830LigozioApr. 11, 19956,230,835Fischer, et al.May 15, 2001